Ultrasensitive and label-free molecular-level detection enabled by light phase control in magnetoplasmonic nanoantennas
Artikel i vetenskaplig tidskrift, 2015

Systems allowing label-free molecular detection are expected to have enormous impact on biochemical sciences. Research focuses on materials and technologies based on exploiting localized surface plasmon resonances in metallic nanostructures. The reason for this focused attention is their suitability for single-molecule sensing, arising from intrinsically nanoscopic sensing volume and the high sensitivity to the local environment. Here we propose an alternative route, which enables radically improved sensitivity compared with recently reported plasmon-based sensors. Such high sensitivity is achieved by exploiting the control of the phase of light in magnetoplasmonic nanoantennas. We demonstrate a manifold improvement of refractometric sensing figure-of-merit. Most remarkably, we show a raw surface sensitivity (that is, without applying fitting procedures) of two orders of magnitude higher than the current values reported for nanoplasmonic sensors. Such sensitivity corresponds to a mass of similar to 0.8 ag per nanoantenna of polyamide-6.6 (n = 1.51), which is representative for a large variety of polymers, peptides and proteins.

Författare

N. Maccaferri

K. E. Gregorczyk

Tvag de Oliveira

M. Kataja

Aalto-Yliopisto

S. van Dijken

Aalto-Yliopisto

Zhaleh Pirzadeh Irannezhad

Chalmers, Teknisk fysik, Bionanofotonik

Alexander Dmitriev

Chalmers, Teknisk fysik, Bionanofotonik

Johan Åkerman

Göteborgs universitet

M. Knez

Basque Foundation for Science (Ikerbasque)

Paolo Vavassori

Basque Foundation for Science (Ikerbasque)

Nature Communications

2041-1723 (ISSN)

Vol. 6 artikel nr 6150- 6150

Ämneskategorier

Fysik

DOI

10.1038/ncomms7150